94 Rodeo TOO MUCH FUEL (rodeo02 and others!)

Hi
New member here.....I'm helping a neighbor work on a 1994 Rodeo 4wd with the 3.2.
It seems to be dumping huge amounts of fuel....the engine bogs down and it absolutely POURS black smoke out the tailpipe!! Then, it kind of clears up and runs better for a few minutes, and then starts with the over-rich condition again. The CEL light is NOT on (?), and it starts easily. The 02 light IS on, but the owner says it's been on for a long time(!).
I tried the AutoZone deal, but they can't read a 94. Any ideas?:banghead:

rodeo02, I have seen posts on here authored by you.......do you have any advice? MAF? This thing runs so rich, the exhaust looks like a diesel!!! I can't imagine how it could possibly be running within any set parameters...possibly a failed ECM??
I will be eternally grateful for any help or input you may have.

I normally work on older American V-8's, mostly Chevys and MoPars, so if anyone needs any advice on them I may be able to help.

THANKS in ADVANCE!!

the 93-94 rodeo the O2 light comes on every 90k as a reminder to change the O2 sensor.

here is a how to on resetting it:

http://www.houlster.com/amigo/how-to.htm#O2_light

I would start by replacing the O2 sensor.

rodeo02, I have seen posts on here authored by you.......do you have any advice?


wow...he's got a following...

The O2 sensor is pretty much the gauge for how rich or lean the engine is running and it reports back to the ECM which makes adjustments to the air/fuel mixture. If the O2 sensor is giving wrong information, that would certainly effect how rich the engine runs. Without seeing the car, I'd guess it has a bad O2 sensor.

I've seen broken O2 sensors on rodeo's.

wow...he's got a following...

Shocks the heck out of me too! Must be my devilish good looks:lol2: NOT!

Joel

tstocker, I'd definately start by checking/cleaning the MAF. An O2 sensor typically wont make an engine run THAT rich, that quick. You've probably seem from prior posts- but MAF's get messed up REAL quick if an oiled/washable or open cone style air filter has ever been used on the rig. A blown fuel pressure regulator diaphragm can also dump raw fuel into the intake and as a last resort, valve timing could have jumped, but if she's running smooth, good power, thats probably not the case.

G/luck
Joel